1. Field of the Invention
The present invention relates to an oil pan for an engine located below a cylinder block of the engine to store engine oil and in which an oil sensor for detecting a parameter of the engine oil is disposed.
2. Description of the Related Art
Japanese Patent Application Laid-open No. 2003-83935 (JP '935) discloses an oil pan having an oil deterioration sensor in a bottom portion thereof for determining a time to change the engine oil for an automobile engine. The oil deterioration sensor detects the degree of deterioration of the engine oil based on a pH value. The oil deterioration sensor includes a sensing section for housing therein a sensing element, and a mounting section for supporting the sensing section. The sensing section is inserted from below through an opening formed in a bottom portion of the oil pan, wherein the mounting section is secured to the bottom portion of the oil pan.
Also, Japanese Patent Application Laid-open No. 11-30115 discloses an oil pan having a baffle plate disposed above the engine oil stored in the oil pan of an engine to suppress any turmoil occurring on the upper surface of the engine oil.
The oil deterioration sensor disclosed by JP '935 includes the sensing section housed in the oil pan and the mounting section exposed to an outside of the oil pan, wherein an oil hole for in-flowing and out-flowing engine oil to pass through is formed in a vicinity of a lower end portion of the sensing section, and an air hole for in-flowing and out-flowing air is formed in a vicinity of an upper end portion of the sensing section. Therefore, if the engine oil in the oil pan rampages and generates a splash, wherein the splashed oil enters the sensing section through the air hole, the level of engine oil in the sensing section changes, leading to a possibility that such a change detrimentally affects the detection accuracy.